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Asian Journal of Andrology ; (6): 86-92, 2023.
Article in English | WPRIM | ID: wpr-970994


We aimed to study radiomics approach based on biparametric magnetic resonance imaging (MRI) for determining significant residual cancer after androgen deprivation therapy (ADT). Ninety-two post-ADT prostate cancer patients underwent MRI before prostatectomy (62 with significant residual disease and 30 with complete response or minimum residual disease [CR/MRD]). Totally, 100 significant residual, 52 CR/MRD lesions, and 70 benign tissues were selected according to pathology. First, 381 radiomics features were extracted from T2-weighted imaging, diffusion-weighted imaging, and apparent diffusion coefficient (ADC) maps. Optimal features were selected using a support vector machine with a recursive feature elimination algorithm (SVM-RFE). Then, ADC values of significant residual, CR/MRD lesions, and benign tissues were compared by one-way analysis of variance. Logistic regression was used to construct models with SVM features to differentiate between each pair of tissues. Third, the efficiencies of ADC value and radiomics models for differentiating the three tissues were assessed by area under receiver operating characteristic curve (AUC). The ADC value (mean ± standard deviation [s.d.]) of significant residual lesions ([1.10 ± 0.02] × 10-3 mm2 s-1) was significantly lower than that of CR/MRD ([1.17 ± 0.02] × 10-3 mm2 s-1), which was significantly lower than that of benign tissues ([1.30 ± 0.02] × 10-3 mm2 s-1; both P < 0.05). The SVM feature models were comparable to ADC value in distinguishing CR/MRD from benign tissue (AUC: 0.766 vs 0.792) and distinguishing residual from benign tissue (AUC: 0.825 vs 0.835) (both P > 0.05), but superior to ADC value in differentiating significant residual from CR/MRD (AUC: 0.748 vs 0.558; P = 0.041). Radiomics approach with biparametric MRI could promote the detection of significant residual prostate cancer after ADT.

Male , Humans , Prostatic Neoplasms/drug therapy , Androgen Antagonists/therapeutic use , Androgens , Neoplasm, Residual , Retrospective Studies , Magnetic Resonance Imaging/methods , Diffusion Magnetic Resonance Imaging/methods
Chinese Journal of Oncology ; (12): 433-437, 2023.
Article in Chinese | WPRIM | ID: wpr-984740


Objective: To investigate the feasibility and value of histogram analysis based on two-dimensional gray-scale ultrasonography in the differential diagnosis of medullary thyroid carcinoma (MTC) and thyroid adenoma (TA). Methods: The preoperative ultrasound images of 86 newly diagnosed MTC patients and 100 TA patients treated in the Cancer Hospital of Chinese Academy of Medical Sciences from January 2015 to October 2021 were collected. Histograms were performed based on the regions of interest (ROIs) delineated manually by two radiologists, thereafter, mean, variance, skewness, kurtosis, percentiles (1st, 10th, 50th, 90th, 99th) were generated. The histogram parameters between the MTC group and the TA group were compared, and the independent predictors were screened by multivariate logistic regression analysis. Receiver operating characteristic (ROC) analysis was used to compare the individual diagnostic efficacy and joint diagnostic efficacy of independent predictors. Results: Multivariate regression analysis showed that mean, skewness, kurtosis and 50th percentile were independent factors. The skewness and kurtosis in the MTC group were significantly higher than those in the TA group, and the mean and 50th percentile were significantly lower than those in the TA group. The area under the individual ROC curve of mean, skewness, kurtosis and 50th percentile is 0.654-0.778. The area under the combined ROC curve is 0.826. Conclusion: Histogram analysis based on two-dimensional gray-scale ultrasonography is a promising tool to distinguish MTC from TA, in which the joint diagnosis value of mean, skewness, kurtosis and 50th percentile is the highest.

Humans , ROC Curve , Diagnosis, Differential , Retrospective Studies , Thyroid Neoplasms/diagnostic imaging , Ultrasonography , Diffusion Magnetic Resonance Imaging/methods
Journal of Central South University(Medical Sciences) ; (12): 76-83, 2023.
Article in English | WPRIM | ID: wpr-971372


OBJECTIVES@#Magnetic resonance diffusion-weighted imaging (DWI) has important clinical value in diagnosis and curative effect evaluation on endometrial carcinoma. How to improve the detection rate of endometrial small lesions by DWI is the research focus of MRI technology. This study aims to analyze the image quality of small field MRI ZOOMit-DWI sequence and conventional single-shot echo-planar imaging (SS-EPI) DWI sequence in the scanning of endometrial carcinoma, and to explore the clinical value of ZOOMit-DWI sequence.@*METHODS@#A total of 37 patients with endometrial carcinoma diagnosed by operation and pathology in the Second Xiangya Hospital of Central South University from July 2019 to May 2021 were collected. All patients were scanned with MRI ZOOMit-DWI sequence and SS-EPI DWI sequence before operation. Two radiologists subjectively evaluated the anatomical details, artifacts, geometric deformation and focus definition of the 2 groups of DWI images. At the same time, the signal intensity were measured and the signal-to-noise ratio (SNR), contrast to noise ratio (CNR), and apparent diffusion coefficient (ADC) of the 2 DWI sequences were calculated for objective evaluation. The differences of subjective score, objective score and ADC value of the 2 DWI sequences were analyzed.@*RESULTS@#The SNR of the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (301.96±141.85 vs 94.66±41.26), and the CNR of the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (185.05±105.45 vs 57.91±31.54, P<0.05). There was no significant difference in noise standard deviation between the ZOOMit-DWI group and the SS-EPI DWI group (P>0.05). The subjective score of anatomical detail and focus definition in the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (both P<0.05). The subjective score of artifacts and geometric deformation of ZOOMit-DWI group was significantly lower than that of the SS-EPI DWI group (both P<0.05). ADC had no significant difference between the ZOOMit-DWI group and the SS-EPI DWI group (P>0.05).@*CONCLUSIONS@#The image quality of ZOOMit-DWI is significantly higher than that of conventional SS-EPI DWI. In the MRI DWI examination of endometrial carcinoma, ZOOMit-DWI can effectively reduce the geometric deformation and artifacts of the image, which is more conducive to clinical diagnosis and treatment.

Female , Humans , Signal-To-Noise Ratio , Endometrial Neoplasms/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Endometrium , Echo-Planar Imaging/methods , Reproducibility of Results
Journal of Central South University(Medical Sciences) ; (12): 68-75, 2023.
Article in English | WPRIM | ID: wpr-971371


OBJECTIVES@#Currently, it is difficult to assess the expression status of hormone receptor (HR) in breast malignant tumors with human epidermal growth factor receptor 2 (HER-2)-positive in the early preoperative stage, and it is difficult to predict whether it is non-invasively. This study aims to explore the value of MRI on the different HR expression status (HR+/HR-) in HER-2 positive breast cancer.@*METHODS@#Thirty patients with HR+ HER-2-positive breast cancer (HR+ group) and 23 patients with HR-HER-2-positive breast cancer (HR- group) from the First Hospital of Hunan University of Traditional Chinese Medicine between January 7, 2015 and November 26, 2021 were selected as subjects, and all the patients were examined by MRI and all were confirmed by surgery or pathological biopsy puncture. The immunohistochemical staining results were used as the gold standard to analyze the basic clinical conditions, peri-lesion conditions and MRI sign characteristics in the 2 groups.@*RESULTS@#There were all significant differences in terms of mass margins, internal reinforcement features, and apparent diffusion coefficient (ADC) values between the HR+ group and the HR- group (all P<0.05). The logistic multivariate regression model showed that: when the lesion presented as a mass-type breast cancer on MRI, the internal enhancement features of the lesion were an independent predictor for differentiation in the 2 types of breast cancer [odds ratio (OR)=5.95, 95% CI: 1.223 to 28.951, P<0.05], and the mass margin (OR=0.386, 95% CI: 0.137 to 1.082, P>0.05) and ADC value (OR=0.234, 95% CI: 0.001 to 105.293, P>0.05) were not the independent predictors in distinguishing the 2 types of breast cancer.@*CONCLUSIONS@#Multiparametric MRI has good diagnostic value for HR expression status in HER-2-positive breast cancer. Combined logistic regression analysis to construct a predictive model may be helpful to the identical diagnosis.

Humans , Female , Breast Neoplasms/surgery , Magnetic Resonance Imaging/methods , Diffusion Magnetic Resonance Imaging/methods , Breast , Magnetic Resonance Spectroscopy , Retrospective Studies
Acta Academiae Medicinae Sinicae ; (6): 60-64, 2022.
Article in Chinese | WPRIM | ID: wpr-927847


Objective To investigate the correlations of diffusion weighted imaging (DWI) with pathological grading,typing and clinical staging of cervical adenocarcinoma. Methods The data of 95 patients with cervical adenocarcinoma from May 2011 to February 2018 in Cancer Hospital Chinese Academy of Medical Sciences were collected for retrospective analysis.Before treatment,conventional MRI and DWI (b=0,800 s/mm2) were performed,and the apparent diffusion coefficient (ADC) value of cervical adenocarcinoma was measured.The ADC values were compared among different pathological grades,types,and clinical stages. Results The mean ADC value was (1.00±0.25)×10-3 mm2/s in the poorly differentiation group,(1.09±0.25)×10-3 mm2/s in the moderately differentiation group,and (1.22±0.20)×10-3 mm2/s in the well differentiation group,which showed significant difference between the poorly and well differentiation groups (P=0.002).The mean ADC values were (1.04±0.24) ×10-3 mm2/s and (1.21±0.26)×10-3 mm2/s in the endocervical adenocarcinoma (usual type) group and mucinous carcinoma group,respectively,which showed significant difference (P=0.005). Conclusions The worse differentiation of cervical adenocarcinoma corresponded to the lower ADC value.The ADC value of mucinous carcinoma was higher than that of endocervical adenocarcinoma (usual type).

Female , Humans , Adenocarcinoma/pathology , Diffusion Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/methods , Retrospective Studies , Uterine Cervical Neoplasms/diagnostic imaging
Singapore medical journal ; : 203-208, 2022.
Article in English | WPRIM | ID: wpr-927278


INTRODUCTION@#This study aimed to evaluate the potential of non-contrast-enhanced magnetic resonance (MR) imaging as an imaging surveillance tool for detection of hepatocellular carcinoma (HCC) in at-risk patients and to compare the performance of non-contrast MR imaging with ultrasonography (US) as a screening modality for the same.@*METHODS@#In this retrospective study, patients diagnosed with HCC between 1 January 2010 and 31 December 2015 were selected from our institution's cancer registry. Patients who underwent MR imaging and had US performed within three months of the MR imaging were included. For each MR imaging, two non-contrast MR imaging sequences - T2-weighted fat-saturated (T2-W FS) sequence and diffusion-weighted imaging (DWI) - were reviewed for the presence of suspicious lesions. A non-contrast MR image was considered positive if the lesion was seen on both sequences. The performance of non-contrast MR imaging was compared to that of hepatobiliary US for the detection of HCC.@*RESULTS@#A total of 73 patients with 108 HCCs were evaluated. Sensitivity of non-contrast MR imaging for the detection of HCC using T2-W FS and DWI was 93.2%, which was significantly higher than that of US, which was 79.5% (p = 0.02). In a subgroup of 55 patients with imaging features of liver cirrhosis, the sensitivity of non-contrast MR imaging was 90.9%, which was also significantly higher than that of US, which was 74.5% (p = 0.02).@*CONCLUSION@#Our pilot study showed that non-contrast MR imaging, using a combination of T2-W FS and DWI, is a potential alternative to US as a screening tool for surveillance of patients at risk for HCC.

Humans , Carcinoma, Hepatocellular/pathology , Contrast Media , Diffusion Magnetic Resonance Imaging/methods , Gadolinium DTPA , Liver Neoplasms/pathology , Magnetic Resonance Imaging/methods , Pilot Projects , Retrospective Studies , Sensitivity and Specificity
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 362-365, 2022.
Article in Chinese | WPRIM | ID: wpr-935811


Objective: To explore the CT and MRI imaging findings of diquat toxic encephalopathy. Methods: CT and MRI imaging features of 10 patients with diquat poisoning encephalopathy who had been clinically diagnosed were retrospectively reviewed. Results: CT was performed in all 10 patients, and MRI was performed in 8 patients. In 10 patients, 7 had positive signs on CT, and 8 patients with MRI examination had abnormal changes in the images. The main CT findings were symmetrical hypodensity in bilateral cerebellar hemisphere, brainstem, thalamus and basal ganglia, and swelling of brain tissue. The main MRI findings were symmetrical lesions and brain edema in the deep nuclei of cerebellar hemisphere, brainstem, thalamus and basal ganglia, low signal on T1WI, high signal on T2WI and T2-FLAIR, and cytotoxic edema on diffusion weighted imaging (DWI) . On review after treatment, both CT and MRI showed resorption of the lesion, which narrowed in size. Conclusion: The imaging findings of diquat poisoning encephalopathy are characteristic and the location of the lesion is characteristic, and CT and MRI have a certain diagnostic value in diquat poisoning encephalopathy, which is important for clinical treatment.

Humans , Brain Diseases , Diffusion Magnetic Resonance Imaging/methods , Diquat , Magnetic Resonance Imaging/methods , Neurotoxicity Syndromes/etiology , Retrospective Studies
Journal of Biomedical Engineering ; (6): 1117-1126, 2022.
Article in Chinese | WPRIM | ID: wpr-970649


Constrained spherical deconvolution can quantify white matter fiber orientation distribution information from diffusion magnetic resonance imaging data. But this method is only applicable to single shell diffusion magnetic resonance imaging data and will provide wrong fiber orientation information in white matter tissue which contains isotropic diffusion signals. To solve these problems, this paper proposes a constrained spherical deconvolution method based on multi-model response function. Multi-shell data can improve the stability of fiber orientation, and multi-model response function can attenuate isotropic diffusion signals in white matter, providing more accurate fiber orientation information. Synthetic data and real brain data from public database were used to verify the effectiveness of this algorithm. The results demonstrate that the proposed algorithm can attenuate isotropic diffusion signals in white matter and overcome the influence of partial volume effect on fiber direction estimation, thus estimate fiber direction more accurately. The reconstructed fiber direction distribution is stable, the false peaks are less, and the recognition ability of cross fiber is stronger, which lays a foundation for the further research of fiber bundle tracking technology.

Brain , White Matter/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Algorithms , Databases, Factual , Image Processing, Computer-Assisted/methods
Asian Journal of Andrology ; (6): 177-182, 2019.
Article in English | WPRIM | ID: wpr-1009665


We aimed to evaluate the feasibility of simultaneous image acquisition of multiple instantaneous switchable scan (MISS) for prostate magnetic resonance imaging (MRI) on 3T. Fifty-three patients were scanned with MRI due to suspected prostate cancer. Twenty-eight of them got histological results. First, two readers assessed the structure delineation and image quality based on images of conventional T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) (CTD). Second, two readers identified the index lesion together, and then, reader one evaluated the contrast of index lesion on T2WI and signal ratio on apparent diffusion coefficient map. Third, they assigned Prostate Imaging Reporting and Data System (PI-RADS) score in consensus for the index lesion. After 4 weeks, the images of MISS were reviewed by the same readers following the same process. Finally, two readers gave preference for image interpretation, respectively. Kappa coefficient, Wilcoxon signed-rank test, paired-sample t-test, Bland-Altman analysis, and receiver operating characteristic (ROC) analysis were used for statistical analysis. The acquisition time of CTD was 6 min and 10 s, while the acquisition time of MISS was 4 min and 30 s. Interobserver agreements for image evaluation were κ = 0.65 and κ = 0.80 for CTD and MISS, respectively. MISS-T2WI showed better delineation for seminal vesicles than CTD-T2WI (reader 1: P < 0.001, reader 2: P = 0.001). The index lesion demonstrated higher contrast in MISS-T2WI (P < 0.001). The PI-RADS scores based on CTD and MISS exhibited high ability in predicting clinically significant cancer (area under curve [AUC] = 0.828 vs 0.854). Readers preferred to use MISS in 41.5%-47.2% of cases. MISS showed comparable performance to conventional technique with less acquisition time.

Adult , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Young Adult , Diffusion Magnetic Resonance Imaging/methods , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Seminal Vesicles/diagnostic imaging
Einstein (Säo Paulo) ; 17(3): eAO4615, 2019. tab, graf
Article in English | LILACS | ID: biblio-1011995


ABSTRACT Objective: To compare qualitatively and quantitatively, in terms of image quality, a new biexponential diffusion sequence protocol with the standard monoexponential diffusion protocol on multiparametric prostate magnetic resonance imaging. Methods: This study had a prospective data collection and cross-sectional analysis. Between August and November 2017, a total of 70 patients who underwent multiparametric prostate magnetic resonance imaging due to clinical suspicion of prostatic neoplasia were recruited. The images obtained were evaluated by two independent readers regarding subjective/qualitative criteria (six criteria) and objective/quantitative criteria (three criteria), always comparing the monoexponential to biexponential acquisition protocols. The results were compared by statistical analysis (interobserver agreement − Gwet coefficient; analysis of the qualitative variables − Stuart-Maxwell test; and analysis of the quantitative variables − Wilcoxon test). Results: After exclusion of four patients, the final sample consisted of 66 patients. A good/excellent inter observer agreement was stablished for subjective criteria (except in one criteria). For the qualitative analysis the amount of good or excellent evaluations was higher for the monoexponential protocol (except in one category), with evidence of significant differences for three criteria (diffusion weighted imaging global quality; diffusion weighted imaging signal-to-noise ratio; and apparent diffusion coefficient signal-to-noise ratio). For the quantitative data analysis, the monoexponential protocol showed less variability of the anteroposterior diameters, meaning less distortion of the images, and better estimated signal-to-noise ratio. Conclusion: In our data, the quality of the images of the monoexponential standard diffusion sequence was qualitatively and quantitatively superior to those of the biexponential diffusion weighted imaging sequence.

RESUMO Objetivo: Comparar qualitativa e quantitativamente, em termos de qualidade de imagem, um novo protocolo de sequência de difusão biexponencial com o protocolo de difusão monoexponencial padrão, em ressonância magnética multiparamétrica da próstata. Métodos: Estudo com coleta prospectiva e análise transversal. Entre agosto e novembro de 2017, foram recrutados 70 pacientes que realizaram ressonância magnética multiparamétrica da próstata, por suspeita de neoplasia prostática. As imagens obtidas por ambas as sequências foram avaliadas por dois leitores independentes, quanto a critérios de avaliação subjetiva/qualitativa (seis critérios) e objetiva/quantitativa (três critérios), sempre comparando os protocolos de aquisição monoexponencial e biexponencial. Os resultados foram comparados por análise estatística (concordância interobservador − coeficiente de Gwet; análise das variáveis qualitativas − teste de Stuart-Maxwell; e análise das variáveis quantitativas − testes de Wilcoxon). Resultados: Após exclusão de quatro pacientes, a amostra final foi composta por 66 pacientes. Uma boa/excelente concordância interobservador foi estabelecida para critérios subjetivos (exceto em um critério). Para a análise qualitativa, a quantidade de avaliações boas ou excelentes foi maior para o protocolo monoexponencial (exceto em uma categoria), com evidências de diferenças significativas para três critérios (qualidade global da imagem ponderada em difusão, relação sinal-ruído na imagem ponderada em difusão e relação sinal-ruído ADC). Para a análise quantitativa dos dados, o protocolo monoexponencial apresentou menor variabilidade dos diâmetros anteroposteriores, o que significou menos distorção das imagens, e melhor relação sinal-ruído estimada. Conclusão: Em nossos dados, a qualidade das imagens da sequência de difusão padrão monoexponencial foi qualitativa e quantitativamente superior àquelas da sequência teste biexponencial.

Humans , Male , Prostatic Neoplasms/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Diffusion Magnetic Resonance Imaging/standards , Reference Standards , Observer Variation , Cross-Sectional Studies , Prospective Studies , Reproducibility of Results , Statistics, Nonparametric , Signal-To-Noise Ratio
São Paulo; s.n; 2018. 88 p. ilust, tabelas.
Thesis in Portuguese | LILACS, Inca | ID: biblio-1248211


Introdução: A Ressonância Magnética (RM) tem se mostrado eficaz na avaliação de resposta à quimioterapia neoadjuvante (QTN) para câncer de mama. A avaliação através do realce dinâmico do contraste (DCE) é a ferramenta mais utilizada na RM para este propósito, porém a aplicação das imagens ponderadas em difusão (DWI) tem recebido especial interesse na atualidade. As sequências em difusão avaliam a mobilidade de moléculas de água no tecido, através do valor do coeficiente aparente de difusão (ADC). Desta forma, após o início de um tratamento quimioterápico, a redução do número de células no leito tumoral é estimada através do aumento do ADC nos exames de RM subsequentes, auxiliando na avaliação de resposta. Objetivo: avaliar o uso da RM-DWI na predição precoce de resposta patológica em pacientes com tumores de mama submetidos ao tratamento com quimioterapia neoadjuvante. Pacientes e métodos: Estudo prospectivo e unicêntrico, em que foram incluídas 62 pacientes com diagnóstico de. câncer de mama, elegíveis para quimioterapia neoadjuvante, admitidas no departamento de Mastologia do A.C.Camargo Cancer Center, no período de janeiro de 2015 a julho de 2016, após aprovação do projeto no comitê de ética em pesquisa e consentimento informado e esclarecido assinado pelas pacientes incluídas no projeto. As pacientes incluídas neste estudo realizaram três exames de RM: um antes (RM1), um após o primeiro ciclo (RM2) e outro após o último ciclo (RM3) de quimioterapia. As taxas de. resposta obtidas pela RM foram avaliadas, considerando a resposta patológica como padrão-ouro. Resultados: A idade das 62 pacientes variou de 27 a 65 anos, com mediana de 45,5 anos. O tamanho tumoral variou de 15 mm a 92 mm, com mediana de 40 mm. Houve predomínio do carcinoma invasivo do tipo não especial (85,5%). Vinte e dois (35,5%) tumores eram triplo negativos, 10 (16,1%) eram superexpressores de HER-2 e 30 (48%). eram subtipo Luminal B. Vinte e quatro (38,7%) tumores apresentaram resposta patológica completa (pCR). A variação do ADC (ADC) entre RM1 e RM2 foi mais elevada para o grupo pCR, com a mediana do ADC de 49% para o grupo pCR e 13% para o grupo não-pCR. Utilizando um ponto de corte de 25% para variação mínima do valor do ADC entre RM1 e RM2, o método apresentou sensibilidade de 83%, especificidade de 84%, VPP de 77%, VPN de 89% e acurácia de 84%. Não houve variação significativa das maiores dimensões tumorais entre a RM1 e RM2. Conclusão: A variação do ADC após o primeiro ciclo de QTN em pacientes com câncer de mama localmente avançado correlacionou-se bem com a taxa de resposta patológica tumoral. Houve um significativo aumento do ADC precedendo a redução da dimensão tumoral. O método é capaz de discriminar com boa. acurácia, logo após o primeiro ciclo, respondedoras de não respondedoras ao tratamento, quando há uma variação mínima de 25% do seu valor

INTRODUCTION: Magnetic Resonance Imaging (MRI) has been shown to be effective in evaluating the response to neoadjuvant chemotherapy (NCT) for breast cancer. Dynamic contrast enhancement (DCE) evaluation is the most used tool in MRI for this purpose, but the application of diffusion weighted images (DWI) has received special interest in the present time. The diffusion sequences evaluate the mobility of water molecules in the tissue, through the value of the apparent diffusion coefficient (ADC). Thus, after the introduction of a chemotherapeutic treatment, the reduction of the number of cells in the tumor bed is estimated by increasing the ADC in the subsequent MR exams, aiding in the evaluation of response. PURPOSE: to evaluate the use of MR-DWI in the early prediction of pathological response in patients with breast tumors submitted to treatment with neoadjuvant chemotherapy. PATIENTS AND METHODS: A prospective and unicentric study was carried out in which 62 patients undergoing NCT admitted in the department of Mastology, were enrolled in the diagnosis of breast cancer, from January 2015 to July 2016. The patients included in this study performed three MR imagings: one before (MR1), one after the first cycle (MR2) and another after the last cycle (MR3) of chemotherapy. The response rates obtained by MR imaging were evaluated, considering the pathological response as gold standard. RESULTS: The 62 patients ranged from 27 to 65 years, with a median age of 45.5 years. The tumor size ranged from 15 to 92 mm, with a median of 40 mm. There was a predominance of invasive carcinoma of no special type (85.5%). Twenty-two (35.5%) tumors were triple negative, 10 (16.1%) were HER-2 overexpression and 30 (48%) were luminal B. Twenty-four (38.7%) tumors presented complete pathological response (pCR). The percent ADC value increase between MR1 and MR2 was higher for the pCR group, with the median ADC of 49% for the pCR group and 13% for the nonpCR group. Using a cut-off point of 25% for minimum increase of the ADC value between MR1 and MR2, the method had a sensitivity of 83%, specificity of 84%, VPP of 77%, NPV of 89% and accuracy of 84% in early prediction of responder to nonresponder to NQT. CONCLUSION: The ADC variation after the first cycle of NQT in patients with locally advanced breast cancer correlated well with the rate of tumor pathological response. There was a significant increase of the ADC value preceding the reduction of the tumor dimension measured with DCE MR images. DWI is able to discriminate with a good accuracy, shortly after the first cycle, non-responder from responders to treatment when there is a minimum variation of 25% of its value

Humans , Female , Adult , Middle Aged , Biopsy, Needle/methods , Breast Neoplasms/drug therapy , Immunohistochemistry , Carcinoma in Situ , Neoadjuvant Therapy , Diffusion Magnetic Resonance Imaging/methods , Prospective Studies
Braz. j. med. biol. res ; 49(1): e4769, 2016. graf
Article in English | LILACS | ID: biblio-951641


We investigated the diagnostic value of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of magnetic resonance diffusion tensor imaging (DTI) in patients with spinal cord compression (SCC) using a meta-analysis framework. Multiple scientific literature databases were exhaustively searched to identify articles relevant to this study. Mean values and standardized mean differences (SMDs) were calculated for the ADC and FA in normal and diseased tissues. The STATA version 12.0 software was used for statistical analysis. Of the 41 articles initially retrieved through database searches, 11 case-control studies were eligible for the meta-analysis and contained a combined total of 645 human subjects (394 patients with SCC and 251 healthy controls). All 11 studies reported data on FA, and 9 contained data related to the ADC. The combined SMDs of the ADC and FA showed that the ADC was significantly higher and the FA was lower in patients with SCC than in healthy controls. Subgroup analysis based on the b value showed higher ADCs in patients with SCC than in healthy controls at b values of both ≤500 and >500 s/mm2. In summary, the main findings of this meta-analysis revealed an increased ADC and decreased FA in patients with SCC, indicating that DTI is an important diagnostic imaging tool to assess patients suspected to have SCC.

Humans , Spinal Cord Compression/diagnosis , Diffusion Magnetic Resonance Imaging/methods , Diffusion Tensor Imaging/methods , Case-Control Studies , Anisotropy , Publication Bias , Early Diagnosis , Data Accuracy
Rev. gastroenterol. Perú ; 35(3): 262-264, July 2015. ilus
Article in English | LILACS, LIPECS | ID: lil-761487


Clostridium difficile is a major cause of antibiotic-associated diarrhea. We report a patient with complicated Clostridium difficile infection (CDI) who developed rapidly progressive acute respiratory distress syndrome (ARDS), for which CDI was the only identifiable source. CDI should be considered in the differential diagnosis for anyone with diarrhea who presents ARDS, especially in high-risk groups such as the elderly, hospitalized patients, or those who have had a history of CDI.

El Clostridium difficile es una de las causas más frecuentes de diarreas asociadas a antibióticos. Reportamos un paciente con infección por Clostridium difficile complicada (CDI) que desarrolló rápida y progresivamente un síndrome de distress respiratorio agudo (ARDS), del cual el CDI fue la fuente única identificable. El CDI debe considerarse en el diagnóstico diferencial de cualquier persona con diarrea que presenta ARDS, especialmente en los grupos de alto riesgo como los ancianos, pacientes hospitalizados o aquellos que han tenido historia precia de DCI.

Humans , Algorithms , Artifacts , Brain/anatomy & histology , Diffusion Magnetic Resonance Imaging/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Sensitivity and Specificity
Rev. bras. enferm ; 68(3): 429-437, maio-jun. 2015. tab
Article in Portuguese | LILACS, BDENF | ID: lil-756537


RESUMOObjetivo:analisar a tendência da epidemia de aids entre 1988 a 2012, em município de tríplice fronteira.Método:estudo ecológico de série histórica realizado com dados do Departamento de Informática do Sistema Único de Saúde.Resultados:foram registrados 1427 casos de aids, sendo 82,1% na faixa etária de 20 a 49 anos e 56% no sexo masculino. A relação homem/ mulher passou de 9/1 para 1/1 e aumentou o número de casos entre indivíduos com mais anos de estudo, com mais de 50 anos e com idade entre 20 e 34 anos. A categoria de exposição mais frequente foi a heterossexual, signifi cativamente maior entre as mulheres; já o uso de drogas injetáveis associou-se ao sexo masculino.Conclusão:buscando abarcar as modificações no cenário epidemiológico da aids, os profissionais de enfermagem devem implementar estratégias de intervenção junto às pessoas identificadas como sendo as mais vulneráveis à infecção pelo HIV.

RESUMENObjetivo:analizar la tendencia de la epidemia de sida desde 1988 hasta 2012 en el municipio de triple frontera.Método:estudio ecológico de series temporales realizado con datos del Departamento de Sistema de Salud de Informática.Resultados:se registraron 1.427 casos de sida, y el 82,1% de 20 a 49 años y 56% en los hombres. La relación hombre/mujer fue de 09.01 a 01.01 y aumentó el número de casos entre personas con más años de escolaridad, con más de 50 años y de 20 a 34 años. La categoría de exposición más frecuente fue la heterosexual, signifi cativamente mayor en mujeres; ya uso de drogas inyectables se asoció con sexo masculino.Conclusión:tratando de aprovechar los cambios en el contexto epidemiológico del sida se evidencia en este estudio, los profesionales de enfermería deben implementar estrategias de intervención para personas con características identifi cadas como más vulnerables a la infección.

ABSTRACTObjective:to analyze the AIDS epidemic trend from 1988 to 2012, in a tri-border area.Method:Ecological time-series study with data from the Department of informatics from the Brazilian Unifi ed Health System (SUS).Results:A total of 1427 cases of AIDS were registered, and 82.1% were aged 20-49 years and 56% in males. The relationship man/woman went from 9/1 to 1/1 and increased the number of cases among individuals with more years of education, also, people aged more than 50 years old the age group from 20 to 34 years old. The most common exposure category was heterosexual, significantly higher among women; on the other hand, drug injection use was associated with male gender.Conclusion:seeking to embrace the changes in the epidemiological scenario of AIDS, nursing professionals should implement intervention strategies for people identified as the most vulnerable to HIV infection.

Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Contrast Media , Diffusion Magnetic Resonance Imaging , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms , Diffusion Magnetic Resonance Imaging/methods , Feasibility Studies , Neoplasm Grading , Neoplasm Staging , Predictive Value of Tests , Prospective Studies , Reproducibility of Results , ROC Curve , Sensitivity and Specificity
São Paulo med. j ; 133(2): 141-150, Mar-Apr/2015. tab, graf
Article in English | LILACS | ID: lil-746650


CONTEXT AND OBJECTIVE: Positron emission tomography with [18]F-fluoro-2-deoxyglucose (FDG-PET/CT) has been advocated as the method of choice for lymphoma staging, since it enables whole-body analysis with high sensitivity for detection of affected areas and because it combines capacities for anatomical and functional assessment. With technological advances, magnetic resonance imaging (MRI) has emerged as an alternative to FDG-PET/CT. This systematic review with meta-analysis aimed to compare whole-body diffusion-weighted MRI (WB-MRI) with FDG-PET/CT for lymphoma staging. DESIGN AND SETTING: Systematic review on diagnostic test accuracy studies conducted at a public university. METHODS: The Medline, Scopus, Embase and Lilacs databases were searched for studies published up to September 2013 that compared WB-MRI and FDG-PET/CT for lymphoma staging. The reference lists of included studies were checked for any relevant additional citations. RESULTS: Six studies that evaluated the initial lymphoma staging in 116 patients were included. WB-MRI and FDG-PET/CT agreed in 90.5% of the cases (κ = 0.871; P < 0.0001). In most of the studies, when there was disagreement between the methods, WB-MRI overstaged in relation to FDG-PET/CT. The sensitivity of WB-MRI and FDG-PET/CT, in comparison with the clinical-radiological standard, ranged from 59 to 100% and from 63 to 100% respectively. CONCLUSION: WB-MRI is a highly sensitive method for initial lymphoma staging. It has excellent agreement with FDG-PET/CT and is a great alternative for managing lymphoma patients, without using ionizing radiation or an intravenous contrast agent. .

CONTEXTO E OBJETIVO: A tomografia por emissão de pósitrons com 2-[18F]-fluoro-2-deoxi-D-glicose (FDG-PET/CT) tem sido defendida como método de escolha para o estadiamento do linfoma por realizar o estudo do corpo inteiro com boa sensibilidade para detecção das áreas acometidas e por combinar as capacidades de avaliação anatômica e funcional. Com os avanços tecnológicos, a ressonância magnética tem se apresentando como alternativa à FDG-PET/CT. Esta revisão sistemática com metanálise visa comparar a ressonância magnética de corpo inteiro (WB-MRI) com difusão com a FDG-PET/CT no estadiamento do linfoma. TIPO DE ESTUDO E LOCAL: Revisão sistemática de estudos de acurácia diagnóstica conduzida em universidade pública. MÉTODOS: Foi conduzida uma busca nos bancos de dados Medline, Embase, Scopus e Lilacs por estudos publicados até setembro de 2013 comparando a WB-MRI com a FDG-PET/CT no estadiamento do linfoma. As referências bibliográficas dos estudos incluídos foram checadas com a finalidade de encontrar citações adicionais relevantes. RESULTADOS: Foram incluídos seis estudos que avaliaram o estadiamento inicial do linfoma de 116 pacientes. A WB-MRI e a FDG-PET/CT concordaram em 90,5% dos casos (κ = 0,871; P < 0,0001). Na maioria dos estudos, quando houve discordância, a WB-MRI estabeleceu estadiamento superior à FDG-PET/CT. A sensibilidade da WB-MRI e da FDG-PET/CT, em relação ao padrão clínico-radiológico, variou de 59% a 100% e de 63% a 100%, respectivamente. CONCLUSÃO: A WB-MRI apresenta alta sensibilidade no estadiamento inicial do linfoma, excelente concordância com a FDG-PET/CT e representa uma ótima alternativa no manejo de pacientes com linfoma, sem utilizar radiação ionizante ou meio de contraste intravenoso. .

Humans , Diagnostic Tests, Routine/methods , Diffusion Magnetic Resonance Imaging/methods , Lymphoma/pathology , Positron-Emission Tomography/methods , Tomography, X-Ray Computed/methods , Whole Body Imaging/methods , Confidence Intervals , Hodgkin Disease/pathology , Hodgkin Disease , Lymphoma, Non-Hodgkin/diagnosis , Lymphoma, Non-Hodgkin/pathology , Lymphoma, Non-Hodgkin , Lymphoma , Neoplasm Staging , Sensitivity and Specificity
Int. braz. j. urol ; 41(1): 137-146, jan-feb/2015. tab, graf
Article in English | LILACS | ID: lil-742861


Objective The aim of this study was to evaluate the capability and the reliability of diffusion-weighted imaging (DWI) in the changes of kidneys occurring after extracorporeal shock wave lithotripsy (ESWL) treatment for renal stones. Materials and Methods A total of 32 patients who underwent ESWL treatment for renal stone disease between June and December 2011 were enrolled in this prospective study. Color Doppler ultrasonography (CDUS) and DWI were performed before and within 24 hours after ESWL. DWI was obtained with b factors of 0, 500 and 1000 s/mm2 at 1.5 T MRI. Each of Resistive index (RI) and ADC values were calculated from the three regions of renal upper, middle and lower zones for both of the affected and contralateral kidneys. Paired sample t test was used for statistical analyses. Results After ESWL, the treated kidneys had statistically significant lower ADC values in all different regions compared with previous renal images. The best discriminative parameter was signal intensity with a b value of 1000 s/mm2. The changes of DWI after ESWL were noteworthy in the middle of the treated kidney (p<0.01). There were no significant difference between RI values in all regions of treated and contralateral kidneys before and after treatment with ESWL (p>0.05). Conclusion DWI is a valuable technique enables the detection of changes in DWI after ESWL treatment that may provide useful information in prediction of renal damage by shock waves, even CDUS is normal. .

Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Diffusion Magnetic Resonance Imaging/methods , Kidney Calculi/therapy , Kidney/radiation effects , Lithotripsy/adverse effects , High-Energy Shock Waves/adverse effects , Kidney , Lithotripsy/methods , Prospective Studies , Reference Values , Reproducibility of Results , Time Factors , Treatment Outcome , Ultrasonography, Doppler, Color
Korean Journal of Radiology ; : 372-390, 2015.
Article in English | WPRIM | ID: wpr-111043


Advances in imaging-based management of acute ischemic stroke now provide crucial information such as infarct core, ischemic penumbra/degree of collaterals, vessel occlusion, and thrombus that helps in the selection of the best candidates for reperfusion therapy. It also predicts thrombolytic efficacy and benefit or potential hazards from therapy. Thus, radiologists should be familiar with various imaging studies for patients with acute ischemic stroke and the applicability to clinical trials. This helps radiologists to obtain optimal rapid imaging as well as its accurate interpretation. This review is focused on imaging studies for acute ischemic stroke, including their roles in recent clinical trials and some guidelines to optimal interpretation.

Humans , Brain/blood supply , Brain Infarction/diagnostic imaging , Cerebral Angiography/methods , Diagnostic Imaging , Diffusion Magnetic Resonance Imaging/methods , Fibrinolytic Agents/therapeutic use , Intracranial Hemorrhages/diagnosis
Korean Journal of Radiology ; : 617-625, 2015.
Article in English | WPRIM | ID: wpr-83663


OBJECTIVE: To investigate the usefulness of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion MRI for the evaluation of femoral head ischemia. MATERIALS AND METHODS: Unilateral femoral head ischemia was induced by selective embolization of the medial circumflex femoral artery in 10 piglets. All MRIs were performed immediately (1 hour) and after embolization (1, 2, and 4 weeks). Apparent diffusion coefficients (ADCs) were calculated for the femoral head. The estimated pharmacokinetic parameters (Kep and Ve from two-compartment model) and semi-quantitative parameters including peak enhancement, time-to-peak (TTP), and contrast washout were evaluated. RESULTS: The epiphyseal ADC values of the ischemic hip decreased immediately (1 hour) after embolization. However, they increased rapidly at 1 week after embolization and remained elevated until 4 weeks after embolization. Perfusion MRI of ischemic hips showed decreased epiphyseal perfusion with decreased Kep immediately after embolization. Signal intensity-time curves showed delayed TTP with limited contrast washout immediately post-embolization. At 1-2 weeks after embolization, spontaneous reperfusion was observed in ischemic epiphyses. The change of ADC (p = 0.043) and Kep (p = 0.043) were significantly different between immediate (1 hour) after embolization and 1 week post-embolization. CONCLUSION: Diffusion MRI and pharmacokinetic model obtained from the DCE-MRI are useful in depicting early changes of perfusion and tissue damage using the model of femoral head ischemia in skeletally immature piglets.

Animals , Male , Arteries/physiopathology , Diffusion Magnetic Resonance Imaging/methods , Disease Models, Animal , Embolism/complications , Epiphyses/blood supply , Femur Head/blood supply , Osteonecrosis/pathology , Pelvic Bones/blood supply , Reperfusion Injury/complications , Swine
Journal of Korean Medical Science ; : 1689-1697, 2015.
Article in English | WPRIM | ID: wpr-198118


This study aimed to evaluate the reproducibility of apparent diffusion coefficient (ADC) measurements in malignant breast masses, and to determine the influence of mammographic parenchymal density on this reproducibility. Sixty-six patients with magnetic resonance findings of the mass were included. Two breast radiologists measured the ADC of the malignant breast mass and the same area on the contralateral normal breast in each patient twice. The effects of mammographic parenchymal density, histology, and lesion size on reproducibility were also assessed. There was no significant difference in the mean ADC between repeated measurements in malignant breast masses and normal breast tissue. The overall reproducibility of ADC measurements was good in both. The 95% limits of agreement for repeated ADCs were approximately 30.2%-33.4% of the mean. ADC measurements in malignant breast masses were highly reproducible irrespective of mass size, histologic subtype, or coexistence of microcalcifications; however, the measurements tended to be less reproducible in malignant breast masses with extremely dense parenchymal backgrounds. ADC measurements in malignant breast masses are highly reproducible; however, mammographic parenchymal density can potentially influence this reproducibility.

Adult , Aged , Aged, 80 and over , Female , Humans , Middle Aged , Algorithms , Breast Neoplasms/pathology , Diffusion Magnetic Resonance Imaging/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Sensitivity and Specificity
Korean Journal of Radiology ; : 906-913, 2015.
Article in English | WPRIM | ID: wpr-50484


OBJECTIVE: Hyperintense acute reperfusion marker (HARM) without diffusion abnormalities is occasionally found in patients with an acute stroke. This study was to determine the prevalence and clinical implications of HARM without diffusion abnormalities. MATERIALS AND METHODS: There was a retrospective review of magnetic resonance images 578 patients with acute strokes and identified those who did not have acute infarction lesions, as mapped by diffusion-weighted imaging (DWI). These patients were classified into an imaging-negative stroke and HARM without diffusion abnormalities groups, based on the DWI findings and postcontrast fluid attenuated inversion recovery images. The National Institutes of Health Stroke Scale (NIHSS) scores at admission, 1 day, and 7 days after the event, as well as clinical data and risk factors, were compared between the imaging-negative stroke and HARM without diffusion abnormalities groups. RESULTS: Seventy-seven acute stroke patients without any DWI abnormalities were found. There were 63 patients with an imaging-negative stroke (accounting for 10.9% of 578) and 13 patients with HARM without diffusion abnormalities (accounting for 2.4% of 578). The NIHSS scores at admission were higher in HARM without diffusion abnormalities group than in the imaging-negative stroke group (median, 4.5 vs. 1.0; p < 0.001), but the scores at 7 days after the event were not significantly different between the two groups (median, 0 vs. 0; p = 1). The patients with HARM without diffusion abnormalities were significantly older, compared with patients with an imaging-negative stroke (mean, 73.1 years vs. 55.9 years; p < 0.001). CONCLUSION: Patients with HARM without diffusion abnormalities are older and have similarly favorable short-term neurological outcomes, compared with the patients with imaging-negative stroke.

Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Blood-Brain Barrier/pathology , Contrast Media , Diffusion Magnetic Resonance Imaging/methods , Image Enhancement/methods , Retrospective Studies , Risk Factors , Stroke/cerebrospinal fluid , Treatment Outcome , United States